Telecommunications providers are facing a more and more dynamic environment. As customer bandwidth requirements increase and more data ports are required the provider must be able to modify and scale their network. In this dynamic environment switching fabrics (example a cross connect or matrix etc) need to be designed to be easily scalable. As the provider modifies and scales their network the installed base of services must not be affected—it must be able to continue to generate revenue while the rest of the network is changed. The dynamic nature of the network also requires any scaling technique to be non-blocking that is any input can be connected to any unused output without affecting other inputs and outputs. The common approach to solving the problem is to use a centralized fabric design (e.g. fabric shelf) and interconnect to the line card ports in a particular fashion.
The limitation of this solution is the centralized fabric design adds more equipment and consequently increases cost in the shelves. Particularly, stacking of card triggers the problems of interconnectivity in the chassis. The centralized fabric design infrastructure does not scale easily (i.e. to expand a system either equipment needs to be torn out or underutilized equipment is initially installed). The centralized fabric design requires more inter-shelf cables to implement. Further, scaling the switch card fabric configuration leads to various complexities in the system.
Therefore, it would be desirable to have a scalable switch fabric card capacity without affecting the existing connectivity in the chassis to overcome the above limitations.